/*
 * Copyright 2014 Google Inc. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.myMinistry.util;

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Formatter;
import java.util.Locale;
import java.util.TimeZone;

import org.joda.time.DateTime;
import org.joda.time.Duration;
import org.joda.time.Period;
import org.joda.time.format.PeriodFormatter;
import org.joda.time.format.PeriodFormatterBuilder;

import com.myMinistry.provider.MinistryContract.UnionsNameAsRef;

import android.annotation.SuppressLint;
import android.content.Context;
import android.database.Cursor;
import android.text.TextUtils;
import android.text.format.DateUtils;

public class TimeUtils {
	public static final SimpleDateFormat dbDateFormat = new SimpleDateFormat("yyyy-MM-dd", Locale.getDefault());
    //private static final int SECOND = 1000;
    //private static final int MINUTE = 60 * SECOND;
    //private static final int HOUR = 60 * MINUTE;
    //private static final int DAY = 24 * HOUR;

    private static final SimpleDateFormat[] ACCEPTED_TIMESTAMP_FORMATS = {
            new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss Z", Locale.US),
            new SimpleDateFormat("EEE MMM dd HH:mm:ss yyyy", Locale.US),
            new SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.US),
            new SimpleDateFormat("yyyy-MM-dd HH:mm:ss Z", Locale.US),
            new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ", Locale.US),
            new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'", Locale.US),
            new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss Z", Locale.US)
    };

    private static final SimpleDateFormat VALID_IFMODIFIEDSINCE_FORMAT =
            new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss Z", Locale.US);

    public static Date parseTimestamp(String timestamp) {
        for (SimpleDateFormat format : ACCEPTED_TIMESTAMP_FORMATS) {
            format.setTimeZone(TimeZone.getTimeZone("GMT"));
            try {
                return format.parse(timestamp);
            } catch (ParseException ex) {
                continue;
            }
        }

        // All attempts to parse have failed
        return null;
    }

    public static boolean isValidFormatForIfModifiedSinceHeader(String timestamp) {
        try {
            return VALID_IFMODIFIEDSINCE_FORMAT.parse(timestamp)!=null;
        } catch (Exception ex) {
            return false;
        }
    }

    public static long timestampToMillis(String timestamp, long defaultValue) {
        if (TextUtils.isEmpty(timestamp)) {
            return defaultValue;
        }
        Date d = parseTimestamp(timestamp);
        return d == null ? defaultValue : d.getTime();
    }

    @SuppressLint("NewApi")
	public static String formatShortDate(Context context, Date date) {
        StringBuilder sb = new StringBuilder();
        Formatter formatter = new Formatter(sb);
        return DateUtils.formatDateRange(context, formatter, date.getTime(), date.getTime(),
                DateUtils.FORMAT_ABBREV_ALL | DateUtils.FORMAT_NO_YEAR,
                PrefUtils.getDisplayTimeZone(context).getID()).toString();
    }

    public static String formatShortTime(Context context, Date time) {
        DateFormat format = DateFormat.getTimeInstance(DateFormat.SHORT);
        TimeZone tz = PrefUtils.getDisplayTimeZone(context);
        if (tz != null) {
            format.setTimeZone(tz);
        }
        return format.format(time);
    }
	
	public static String getTimeLength(Calendar start, Calendar end, String h, String m) {
		Duration dur = new Duration(new DateTime(start), new DateTime(end));
		Period period = dur.toPeriod();
		
		PeriodFormatter retVal = new PeriodFormatterBuilder()
									.printZeroNever()
									.appendHours()
									.appendSuffix(h)
									.appendSeparator(" ")
									.appendMinutes()
									.appendSuffix(m)
									.toFormatter();
		
		return retVal.print(period);
	}
	
	public static String getTimeLength(Cursor cursor, String h, String m, boolean showMinutes) {
		SimpleDateFormat saveDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm", Locale.getDefault());
		Calendar start = Calendar.getInstance(Locale.getDefault());
		Calendar end = Calendar.getInstance(Locale.getDefault());
		
		Duration dur = new Duration(null, null);
		Duration durchange = new Duration(null, null);
		
		for(cursor.moveToFirst();!cursor.isAfterLast();cursor.moveToNext()) {
			try {
				start.setTime(saveDateFormat.parse(cursor.getString(cursor.getColumnIndex(UnionsNameAsRef.DATE_START))));
			} catch (Exception e) {
				start = Calendar.getInstance(Locale.getDefault());
			}
			try {
				end.setTime(saveDateFormat.parse(cursor.getString(cursor.getColumnIndex(UnionsNameAsRef.DATE_END))));
			} catch (Exception e) {
				end = Calendar.getInstance(Locale.getDefault());
			}
			
			durchange = new Duration(new DateTime(start), new DateTime(end));
			dur = dur.withDurationAdded(durchange, 1);
		}
		
		cursor.close();
		
		PeriodFormatter retVal;
		
		if(showMinutes) {
			retVal = new PeriodFormatterBuilder()
						.printZeroRarelyFirst()
						.appendHours()
						.appendSuffix(h)
						.appendSeparator(" ")
						.appendMinutes()
						.appendSuffix(m)
						.toFormatter();
		}
		else {
			retVal = new PeriodFormatterBuilder()
						.printZeroAlways()
						.appendHours()
						.appendSuffix(h)
						.toFormatter();
		}
		
		return retVal.print(dur.toPeriod());
	}
}